AJI Posted April 29, 2009 Share Posted April 29, 2009 Did I read somewhere that running in TTC mode (the easy reversable mod) would show up any faults with the VSV valves?? I have a boost problem at the moment whereby turbo 2 is not spooling. Similar happened last year and was found to be a faulty solenoid on the Blitz SCB i-colour controller. But I have had the solenoid off the car and tested it by connecting 12v and I can hear the solenoids 'clicking'..... so am I safe to say that they are ok? I have mostly ruled out split or disconnected hoses as I simply can not see anything unusual. Had a good feel around etc. (oo err). But probably could do with disconnecting each one, checking, and then re-connecting....such a pain in the @rse. So I am guessing that the next thing to check easily are the VSVs. Is it easier to do a quick TTC mod and check the VSVs that way or to take off each VSV and perform the tests shown on here : http://www.max-boost.co.uk/max-boost/resources/SUPRA_MKIV/IACV_tests.pdf Many thanks for any help. Quote Link to comment Share on other sites More sharing options...
bignum Posted April 29, 2009 Share Posted April 29, 2009 Its easier to do the ttc mod yes as there`s only 2 pipes to swap over, could be a stuck egbv or the actuator controlling it. Quote Link to comment Share on other sites More sharing options...
Scott Posted April 29, 2009 Share Posted April 29, 2009 If you run the TTC mod it will show if there is any issues with the entire vac system. It could be a fault with a VSV or the pressure tank. Its the easiest way to narrow down your options though. If you still don't get boost try holding the EGCV actuator and IACV actuator. I just jammed a piece of metal into each for a quick check. Quote Link to comment Share on other sites More sharing options...
AJI Posted April 29, 2009 Author Share Posted April 29, 2009 Great... will give those options a try. Quote Link to comment Share on other sites More sharing options...
AJI Posted April 30, 2009 Author Share Posted April 30, 2009 Well, gave the TTC a go tonight and still only getting about 1 bar pressure. So this now points to a leak somewhere in the system... or a problem with one of the VSVs. How much are VSVs to buy new out of interest? (p.s. on the TTC mod shown here : http://mkiv.supras.org.nz/articles/andy.htm ... on the 3rd image down where it says 'cap these to keep dirt out'.... I've basically put gaffer-tape over them... am I right in thinking this will not have any effect on the TTC mode?) Quote Link to comment Share on other sites More sharing options...
Scott Posted April 30, 2009 Share Posted April 30, 2009 Your getting one bar of boost? The 2nd turbo is coming online then. What were the actuators like after taking the car for a run? Were they still held open? Its got nothing to do with the VSV's if its still not working. The VSV's have been taken out of the equation. Quote Link to comment Share on other sites More sharing options...
AJI Posted April 30, 2009 Author Share Posted April 30, 2009 ah..ok...so then it must either be a hidden split hose or a leak in the pressure tank. Cheers. Anybody know of a place in the north west (or north east) where I can get a pressure test done? Quote Link to comment Share on other sites More sharing options...
Scott Posted April 30, 2009 Share Posted April 30, 2009 ah..ok...so then it must either be a hidden split hose or a leak in the pressure tank. Cheers. Anybody know of a place in the north west (or north east) where I can get a pressure test done? No, where are you getting your fault finding from? You seem to be jumping to conclusions and i can't follow your thinking. Did the system hold pressure once stopped? Quote Link to comment Share on other sites More sharing options...
AJI Posted April 30, 2009 Author Share Posted April 30, 2009 Well after reading a few posts here and there I am lead to believe that using the TTC mod will show up if the pressure system is working or not.... if it is then TTC will work, if not then problem with pressure system. As I am not getting 1.25bar with TTC as I was formally getting with stock sequential setup (when it was working properly), then my line of thought is that pressure is being lost somewhere in the 'system'. I had very similar problem about a year or two ago which turned out to be the solenoid on my Blitz boost controller. In effect turbo2 was not coming online even though I was just hitting 1 bar. I know 1st turbo should only be producing about 0.8bar.... but I have blitz exhaust and fully decatted....so 1st turbo should be able to produce a bit higher.... is this correct? So.... if its not the hoses or the pressure tank, then what else? .... turbo 2 failed? I thought if this happened then it would be a bit more dramatic... as nothing really noticable happened.... I basically drove to work where everything was fine. When home-time came I started the car and let her warm up. About 10mins later I was on the dual carriageway and gave it some beans and only then noticed the car felt sluggish and on checking the boost controller it was only showing 1bar. The 1bar is like a slow 'spike' by the way..it doesn't really hold it at that pressure and drops back to about 0.9bar (or less). (Which should be about correct for a uk-spec on full decat... but please correct me if I'm wrong). ------------------ When you ask 'did the system hold the pressure once stopped'.... how do I check this? Thanks for the help by the way...its much appreciated. Quote Link to comment Share on other sites More sharing options...
Scott Posted April 30, 2009 Share Posted April 30, 2009 Ok. With TTC mode you might get slightly less boost than you do in sequential. The 1st turbo only produces 0.7bar and then up to 0.8bar with bpu (approx). If you are seeing 1bar its either seriously overboosting or the 2nd turbo IS coming online. After running TTC the IACV and the EGCV should be held open. If they are this confirms that the sequential vac system is fine along with the pressure tank. If they are closed then there is a leak in the vac system. Remember that the vac system is seperate from the boost pressure. So.. 1st things 1st. Are the actuators held open or have they closed? Quote Link to comment Share on other sites More sharing options...
AJI Posted May 1, 2009 Author Share Posted May 1, 2009 Will check the actuators tonight after work. Cheers. Quote Link to comment Share on other sites More sharing options...
AJI Posted May 1, 2009 Author Share Posted May 1, 2009 Actuators are closed. I then tied the IACV and the EGCV open as per this thread suggestion : http://www.mkivsupra.net/vbb/showthread.php?t=83943&highlight=testing+actuators But even with this mod the 2nd turbo was not fully coming online and only 0.9-1.0 bar boost is being developped. So I guess this mean it is not a problem with the pressure tank? And points to a leak in the vac system as suggested. Now, how do I go about checking the vac system for leaks? and possible repair? Cheers. Quote Link to comment Share on other sites More sharing options...
Scott Posted May 1, 2009 Share Posted May 1, 2009 Actuators are closed. I then tied the IACV and the EGCV open as per this thread suggestion : http://www.mkivsupra.net/vbb/showthread.php?t=83943&highlight=testing+actuators But even with this mod the 2nd turbo was not fully coming online and only 0.9-1.0 bar boost is being developped. So I guess this mean it is not a problem with the pressure tank? And points to a leak in the vac system as suggested. Now, how do I go about checking the vac system for leaks? and possible repair? Cheers. Was this in TTC mode you tried it? If the actuators were both closed after running in TTC mode then there is something wrong with the vac lines or the pressure tank. You need to get that sorted before going any further. Quote Link to comment Share on other sites More sharing options...
AJI Posted May 1, 2009 Author Share Posted May 1, 2009 Yes this was still in TTC mode. I thought though, by doing the mod whereby I tie open the IACV and the EGCV, that this would eliminate the pressure tank being the problem? So only leaving the vac lines to be the issue? Quote Link to comment Share on other sites More sharing options...
Scott Posted May 1, 2009 Share Posted May 1, 2009 If you tied them open then its nothing to do with the vac system. Its either a leak in the intercooler/turbo piping or the 2nd turbo has lost a few fins. Quote Link to comment Share on other sites More sharing options...
AJI Posted May 1, 2009 Author Share Posted May 1, 2009 Thanks for the help Scott. I will check intercooler and all relevant piping tomorrow. Quote Link to comment Share on other sites More sharing options...
bignum Posted May 2, 2009 Share Posted May 2, 2009 Have a look at this thread,http://www.mkivsupra.net/vbb/showthread.php?t=78568&highlight=pressure+testing+intercooler+pipework&page=2 Pressurize the system then use some washing up liquid/water mix and squirt on various pipes using a large syringe, you can try it by revving the engine from the throttle cable but it`ll be more difficult hearing an air leak and probably piss the neighbours off. Quote Link to comment Share on other sites More sharing options...
AJI Posted May 2, 2009 Author Share Posted May 2, 2009 Thanks Bignum. What a great test !! [image taken from link above] I'm guessing Halfrauds sell these? Today: I checked the intercooler pipe-work and all is connected properly (well from what I could see after taking off the wheel arch shroud and jacking the car up etc.) Next step is this great looking pressure test...with huge tube hanging out of the car. Quote Link to comment Share on other sites More sharing options...
AJI Posted May 2, 2009 Author Share Posted May 2, 2009 If the above test shows a leak... then its all about locating the leak. The washing up liquid might be a hard test to do when I can not fully see the bottom intercooler pipe behind the front bumper. (Hopefully I can hear it instead). Anybody know of a coloured gas I could introduce to the pressure test so that it can spray out of the leak and be seen? (Similar to the way they check for air-con leaks) Quote Link to comment Share on other sites More sharing options...
AJI Posted May 7, 2009 Author Share Posted May 7, 2009 Well I tried this pressure test tonight but the innertube wouldn't even start to fill up. It seemed as though any pressure I was putting into it was being lost straight away. I had good seals on both sides of the innertube and I checked behind the radiator for the bottom hose that runs behind the front bumper, but couldn't see anything hanging off. I then checked the hose clip connection on the passenger side of the car and all seemed ok. I looked across from the passenger side to view the connection to the intercooler and it looks connected. What is the easiest way to get at the intercooler? Quote Link to comment Share on other sites More sharing options...
Scott Posted May 7, 2009 Share Posted May 7, 2009 either a ramp, a pit or by removing the front bumper. To start off its probably best just to remove both of the headlights and see what you can see from there. Quote Link to comment Share on other sites More sharing options...
AJI Posted May 7, 2009 Author Share Posted May 7, 2009 Just been thinking that if the leak is soo bad as to not even start to create any pressure in the innertube then how is the car developing about 1bar boost? .... or would it still create such a boost irrelevant of such a leak? So it is possible to get at the intercooler without having to remove the front bumper? Quote Link to comment Share on other sites More sharing options...
Scott Posted May 7, 2009 Share Posted May 7, 2009 either a ramp, a pit or by removing the front bumper. To start off its probably best just to remove both of the headlights and see what you can see from there. So it is possible to get at the intercooler without having to remove the front bumper? Lol, as above. Ramp, pit or for a bit of access remove the headlights. Quote Link to comment Share on other sites More sharing options...
AJI Posted May 8, 2009 Author Share Posted May 8, 2009 say for example I wanted to take off my upgraded SMIC and replace it back with my stock SMIC....is that possible by working on ramps? Appologies for all these mundaine questions.... I'm wanting to fully sort the problem myself ...in labour work that is...(for once). Quote Link to comment Share on other sites More sharing options...
Scott Posted May 8, 2009 Share Posted May 8, 2009 Ahh sorry, i was thinking you had a front mount. I've never even seen a side mount so i can't say. Hopefully someone will be along that can help out Quote Link to comment Share on other sites More sharing options...
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